Depto. Química Orgánica

Brief History
1820 -1830

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15/07/2017
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Friedrich Wöhler managed to synthesize an organic compound, urea, from an inorganic compound, thus putting an end to the vitalist theory of Jöns Jacob Berzelius. Wöhler discovered that urea and ammonium cyanate have the same atomic composition, but very different chemical properties. It can be said that this fact marks the discovery of isomerism, since urea and ammonium cyanate have different formulas, CO(NH2)2 and NH4CNO, respectively, and the same elemental composition.

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A pioneer in the field of organic chemistry, Wöhler is famous for his synthesis of the organic compound called urea (which is extracted from urine). Through his contribution it was demonstrated, contrary to the scientific thinking of the time, that a product of vital processes could be obtained in the laboratory from inorganic matter. He also carried out important research on uric acid and bitter hazelnut oil in collaboration with the German chemist Justin von Liebig. He also isolated two chemical elements: aluminum and beryllium. He discovered calcium carbide and from it obtained acetylene. He also developed the method for preparing matchstick that is still used today. In 1830 he determined that the element erythronium discovered by Andrés Manuel del Río in Mexico in 1801 and the vanadium discovered by Nils Gabriel Sefström in Sweden 30 years later were the same. He wrote several textbooks on organic and inorganic chemistry.
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Around 1820 Elemental Analysis became a standard technique in Chemistry. The most relevant researcher in this technique was William Prout. In 1817 he carried out the analysis of urea, obtaining 46.65% nitrogen, 26.65% oxygen, 19.975% carbon and 6.67% hydrogen. Modern values are 46.67% N, 26.67% O, 20.0% C, and 6.67% H.

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William Prout (1785 – 1850) was an English chemist, physicist and natural theologian. Fellow of the Royal Society, his main scientific contribution was what was known as the Prout Hypothesis. The Prout Hypothesis was an attempt made at the beginning of the 19th century to explain the existence of several chemical elements through a hypothesis about the internal structure of the atom. In 1815 and 1816, the English chemist William Prout published two articles in which he observed that the atomic weight that had been established for the elements known until then seemed to be an absolute multiple of the atomic weight of hydrogen. Consequently, he established the hypothesis that the hydrogen atom was the only truly fundamental one, and that the atoms of the other elements were actually groupings of several hydrogen atoms.